I recently heard a researcher talk about studies that suggest the use of popular electronic media devices may lead to diabetes. If that is the case we are in real trouble. Not long ago I also read an article about the relationship between diabetes and Alzheimer's disease. And there's more. It is not a secret that people with diabetes are prone to obesity and heart disease.
So, what is the connection? It is too early to say, it seems a natural hormone made in the body called melatonin may be a link. Melatonin promotes sleepiness and is produced by the pineal gland and other tissues in the evening as it gets dark. In the morning as the sun rises melatonin decreases. This is referred to as circadian rhythm.
The disruption of circadian rhythms may increase the risk of Type 2 Diabetes by accelerating the loss of beta-cell function and mass. The beta cells of the pancreas is where insulin is made in the body. Taking out the pineal gland has been shown to lead to the development of high blood sugars associated with decreased beta-cell function.
I used to think that melatonin was only helpful for people by making them sleep better. As it turns out melatonin has a much broader effect on the body. An interesting feature of melatonin is its ability to act as a potent antioxidant. Antioxidants help keep the immune system working properly and prevent tissue damage all over the body. This could be one of the reasons inadequate melatonin may lead to breast cancer, irritable bowel syndrome, heart disease, diabetes and even Alzheimer's disease.
The mechanism of beta-cell failure in Type 2 Diabetes shares many parallels with neurodegenerative (destruction of nerve or brain cells) diseases such as Alzheimer disease. Melatonin has been shown to promote cell survival, mainly in response to Alzheimer beta-amyloid-induced cell death, the type of cell destruction caused by the plaque formation on brain cells.
Several studies have showed that melatonin levels are lower in patients with Alzheimer's compared to age-matched control subjects. Changes in melatonin secretion contribute to the frequent symptoms of sleep disruption, nightly restlessness and sundowning seen in Alzheimer's patients. Apparently long-term administration of melatonin in the dose of around 6 mg per day improves sleep quality.
Anyone taking melatonin with other medications should check with their doctor or pharmacist to be sure there is no undesirable interaction or interference.
Since light decreases melatonin secretion it would seem those working night shifts would have some negative health consequences. Studies involving nurses and correctional officers have shown an increased incidence of cancer, diabetes, heart disease, fractures, insomnia, obesity, gastrointestinal problems, ulcers, depression, and other conditions. A 2011 study found a 20 percent increase in Type 2 diabetes rates among nurses who worked nights for only three years. Those who worked nights for 20 years had a 60 percent greater chance of developing the disease.
Diabetes rates soar among those who work nights in comparison to their nine-to-five compatriots. A 2011 study found a 20 percent bump in Type 2 diabetes rates among nurses who worked nights for just three years. Those who kept it up for 20 years had a 60 percent greater chance of developing the disease. Whether this is due to decreased melatonin levels or to changes in lifestyle has yet to be determined.
A study done at a research institute in New York found that, "...a two-hour exposure to light from self-luminous electronic displays can suppress melatonin by about 22 percent. Stimulating the human circadian system to this level may affect sleep in those using the devices prior to bedtime. This is especially worrisome in populations such as young adults and adolescents, who already tend to be night owls." The researchers recommended dimming these devices at night as much as possible to minimize melatonin suppression, and limiting the amount of time spent using these devices prior to bedtime.
Chuck Newcomb, MS, RD, CDE is a consulting registered dietitian currently providing medical nutrition therapy services for Memorial Hospital Los Banos. He has a masters of science in clinical nutrition from New York University. E-mail questions to the Attention of ChuckRD at: MHALosBanos@SutterHealth.org or on his website MySmartRD.com.